Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network™

Open Access. Powered by Scholars. Published by Universities.®

Discipline
Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 123391 - 123420 of 1114197

Full-Text Articles in Entire DC Network

Eco-Friendly Web Search Engines: Fit For Purpose?, Marydee Ojala Jul 2023

Eco-Friendly Web Search Engines: Fit For Purpose?, Marydee Ojala

Midwest Business Librarian Summit (MBLS)

No abstract provided.

Go to article

Mathematical Identities And Tracking: An Exploration Of Efficacy In Children And Women, Emma Hagan Jul 2023

Mathematical Identities And Tracking: An Exploration Of Efficacy In Children And Women, Emma Hagan

Education | Master's Theses

This study seeks to understand the impact of elementary school mathematical identities and mathematics tracking on the identities of women and girls. “Tracking” is an institutionalized education method developed in the 1960s and 1970s in which schools sort their students into smaller class-sized groups based on their observed achievement (Domina et al., 2016). Too often, when students test onto the lower track, they are confronted with a sense of futility and a lack of self-efficacy (Domina, Hanselman, Hwang & McEachin, 2016; Houtte & Stevens, 2015). Further, in STEM disciplines, students who identify as female report lower self-efficacy rates than those …

Go to article

Predicting Active Foot Contact In The Acceleration Phase Of Athletic Sprinting Through Accelerometer Measurements, Marvin Zedler, Veit Schopper, Wolfgang Potthast, Jan-Peter Goldmann Jul 2023

Predicting Active Foot Contact In The Acceleration Phase Of Athletic Sprinting Through Accelerometer Measurements, Marvin Zedler, Veit Schopper, Wolfgang Potthast, Jan-Peter Goldmann

ISBS Proceedings Archive

Active foot contact (absence of a braking impulse) during the acceleration phase of athletic sprinting is associated with the motion of the foot before touchdown (TD). Since the identification of braking impulses through force plate measurements is cost-expensive, the aim of this study was to develop a machine learning algorithm to predict active foot contact occurrences based on ankle-mounted accelerometer measurements. Ten recreationally active athletes (three females, seven males) performed 30 sprint-block-starts each, which were used as input to the machine learning model. Model performance was assessed by the AUC for both validation (AUC = 0.96) and testing (AUC = …

Go to article

Skilled Riders Manage Horse Gait Complexity Through A Gait Transition Whilst Also Maintaining Stable Horse-Rider Coordination Variability, Celeste A. Wilkins, Franky Mulloy Jul 2023

Skilled Riders Manage Horse Gait Complexity Through A Gait Transition Whilst Also Maintaining Stable Horse-Rider Coordination Variability, Celeste A. Wilkins, Franky Mulloy

ISBS Proceedings Archive

Equestrian riders aim to cue smooth transitions between horse gaits. This study aimed to investigate whether competitive horse rider (n=10) decrease horse gait regularity and increase horse-rider coordination variability in the region of a gait transition (n=6; both walk-trot, and trot-canter) relative to baseline walk, trot and canter. Resultant accelerations from IMUs affixed to the horse’s girth and rider’s pelvis were calculated. Horse gait regularity was quantified as multiscale sample entropy (MSSE) of the pelvis. Horse-rider coordination variability (Coordvar) was quantified as the standard deviation of the horse-rider continuous relative phase. Pre-transition MSSE did not increase; post-transition MSSE …

Go to article

Biomechanics Student’S Learning And Perceptions Of Learning Due To The Covid-19 Pandemic And Associated Mitigation, Brian J. Wallace, Duane Knudson Jul 2023

Biomechanics Student’S Learning And Perceptions Of Learning Due To The Covid-19 Pandemic And Associated Mitigation, Brian J. Wallace, Duane Knudson

ISBS Proceedings Archive

The purpose of this study was to assess the effects of the COVID-19 pandemic and associated mitigation protocols on student learning and perceptions of learning in a biomechanics course. Students (n=31) enrolled in a three credit-hour biomechanics class in the Spring 2022 semester participated. Six questions related to the effects of mitigation protocols on student perceptions of learning. Three questions asked about to course-related student behaviours. Learning scores (g) were similar to those previously reported. Students believed that mitigation negatively affected getting to know and communicate with classmates (>50%), they had to implement different learning strategies (55%), and learning …

Go to article

Gravel Bike Vibrations, Josef Viellehner, Wolfgang Potthast Jul 2023

Gravel Bike Vibrations, Josef Viellehner, Wolfgang Potthast

ISBS Proceedings Archive

TThe purpose of this pilot study was to explore the vibration exposure of Gravel bikes at different tire pressures. Therefore, 9 cyclists (73.7 ± 10.2 kg, 1.78 ± 0.06 m) rode a 150 m flat gravel section at a constant speed of 25 km/h with three tire pressure conditions (1.5, 2.5, 3.5 bar). Horizontal and vertical accelerations at the front dropout (FDO) and rear dropout (RDO) were recorded. Reducing the tire pressure from 3.5 to 1.5 bar resulted in a significant decrease in the resulting acceleration at the FDO from 3.41 ± 0.18 g to 2.07 ± 0.07 g …

Go to article

Two And Three-Dimensional Assessments Of Lower-Limb Kinematics In Underwater Fly Kick, Isobel M. Thompson Miss, Dominic A. Hudson Prof., Martin Warner Dr, Joseph Banks Dr, Oliver Logan Jul 2023

Two And Three-Dimensional Assessments Of Lower-Limb Kinematics In Underwater Fly Kick, Isobel M. Thompson Miss, Dominic A. Hudson Prof., Martin Warner Dr, Joseph Banks Dr, Oliver Logan

ISBS Proceedings Archive

The purpose of this study was to compare sagittal plane lower limb kinematics of underwater fly kick measured using two and three-dimensional methods. Eight male participants (average FINA points score 801±138) completed underwater fly kick trials, recorded using a six camera Qualisys underwater system. Each trial was analysed using both two and three-dimensional methods. Lower-limb angles were significantly underestimated using two-dimensional methods, particularly at the hip where flexion and range of motion reduced by 13.73 degrees and 15.91 degrees respectively. The ankle and hip produce a large amount motion in the transverse and frontal planes. The results of two-dimensional analyses …

Go to article

Relationship Between Kinematic Characteristics And Free-Throw Shooting Precision: Markerless Motion Capture Analysis, Tylan Templin, Dimitrije Cabarkapa, Jonathan Miller, Damjana Cabarkapa, Andrew Fry, Travis Eliason, Lance Frazer, Omar Medjaouri, David Chambers, Kase Saylor, Daniel Nicolella Jul 2023

Relationship Between Kinematic Characteristics And Free-Throw Shooting Precision: Markerless Motion Capture Analysis, Tylan Templin, Dimitrije Cabarkapa, Jonathan Miller, Damjana Cabarkapa, Andrew Fry, Travis Eliason, Lance Frazer, Omar Medjaouri, David Chambers, Kase Saylor, Daniel Nicolella

ISBS Proceedings Archive

The search for aspects of basketball shooting that characterize successful performance is an area of focus for sports biomechanists. However, the systematic evaluation of these key elements during shooting practice is limited due to the time it takes to collect and/or process the data. Thus, the purpose of the present study was to evaluate the relationship between some of the key kinematic variables extracted from a markerless motion capture system on free-throw shot performance. Multivariable linear regression analysis indicated that shot plane alignment, trunk rotation, entry angle, and timing of elbow extension were some of the key contributors to free-throw …

Go to article

Affordance And Its Role In Sepaktakraw Kuda And Sila Serve Non-Planar Kicking Techniques – A Preliminary Qualitative Analysis For Coaching Implication, Ian Harris Sujae, Wan Rizal Wan Zakariah, Chin Yong Alexander Ong, Syahriall Bakhtiar, Joseph Hamill Jul 2023

Affordance And Its Role In Sepaktakraw Kuda And Sila Serve Non-Planar Kicking Techniques – A Preliminary Qualitative Analysis For Coaching Implication, Ian Harris Sujae, Wan Rizal Wan Zakariah, Chin Yong Alexander Ong, Syahriall Bakhtiar, Joseph Hamill

ISBS Proceedings Archive

This study aimed to establish the affordance and its role in Sepaktakraw serve for coaching implications. Five successful kuda and sila trials performed by two trained male players, captured using a high-speed optical camera system, were analyzed. Variations in kicking limb hip-knee joint coordination to impact suggest ball placements be an affordance in Sepaktakraw serve. This affords what the server must do to ensure optimal foot-to-ball impact velocities without compromising ball velocities. With differences in kicking limb length, this coordination becomes player specific, and the ability to adapt and adjust his coordination pattern depends on such affordance. Servers must vary …

Go to article

Validation Of An Inertial Measurement Unit Based Estimation Of Trunk Motion In Sit-Skiing: A Pilot Study, Anna C. Severin, Gertjan Ettema, Jan Kocbach, Jørgen Danielsen Jul 2023

Validation Of An Inertial Measurement Unit Based Estimation Of Trunk Motion In Sit-Skiing: A Pilot Study, Anna C. Severin, Gertjan Ettema, Jan Kocbach, Jørgen Danielsen

ISBS Proceedings Archive

Sagittal plane trunk movement is important for producing propulsive force when sit-skiing. We aimed to validate the use of inertial measurement units for measuring sagittal plane trunk movements during sit-skiing in the field. Able-bodied participants (n=4) performed 30 seconds of sit-skiing in a kneeling position on a treadmill while one AdMos IMU sensor (on the upper back) and 4 reflective markers on the trunk recorded kinematics. A secondary validation was performed with 4 sensors and markers attached to a rigid body, which was rotated to mimic the trunk during sit-skiing. For the rigid body, the root mean square error was

Go to article

Measuring Instantaneous Velocity In Four Swim Strokes Using An Automatic Head Tracking System: A Comparison Study, Michelle Scott, Nathan Elsworthy, Marc Elipot, Victoria Brackley, Crystal O. Kean Jul 2023

Measuring Instantaneous Velocity In Four Swim Strokes Using An Automatic Head Tracking System: A Comparison Study, Michelle Scott, Nathan Elsworthy, Marc Elipot, Victoria Brackley, Crystal O. Kean

ISBS Proceedings Archive

This study compared instantaneous swimming velocity from an automated video-based system to a tethered speedometer. Twenty-two state- and national-level swimmers (7 M, 15 F; 14.5 ± 2.5 yrs) swam 25 m of each stroke at maximal intensity. Bland-Altman plots showed good agreement between systems for backstroke and freestyle but poorer agreement for butterfly and breaststroke. The RMS error was also lower in backstroke and freestyle compared to butterfly and breaststroke. The differences in systems may be explained by the different body segments tracked by each system (head vs hips) and with differences being more apparent during butterfly and breaststroke due …

Go to article

Hip And Lumbosacral Joint Centre Locations In Asian Population: Biases By Existing Regressions And Development Of New Methods, Natsuki Sado, Takeshi Edagawa, Toshihide Fujimori, Shogo Hashimoto, Yoshikazu Okamoto, Takahito Nakajima Jul 2023

Hip And Lumbosacral Joint Centre Locations In Asian Population: Biases By Existing Regressions And Development Of New Methods, Natsuki Sado, Takeshi Edagawa, Toshihide Fujimori, Shogo Hashimoto, Yoshikazu Okamoto, Takahito Nakajima

ISBS Proceedings Archive

Accurate prediction of the lumbosacral and hip joint centres (LSJC, HJC) is crucial for the analysis of lumbo-pelvic-hip dynamics in various movements. Here we show that pre-existing regressions proposed by European research groups produce biased estimates of the LSJC and HJC in Japanese males and females (n = 23, 24), and that the biases in LSJC depend on sex. When compared to locations directly measured by MRI, the pre-existing regressions estimated the LSJC to be more posterior in males and more inferior and posterior in females, and the HJC to be more medial for both sexes. We suggest the …

Go to article

Evaluating The Combined Effect Of Neck Muscle Strength And Hockey Goaltender Helmet Liners In Mitigating Concussion Risk During Simulated Horizontal Head Impacts, Nicholas Renyard, Derek Kivi, Paolo Sanzo, Meilan Liu, Carlos Zerpa Jul 2023

Evaluating The Combined Effect Of Neck Muscle Strength And Hockey Goaltender Helmet Liners In Mitigating Concussion Risk During Simulated Horizontal Head Impacts, Nicholas Renyard, Derek Kivi, Paolo Sanzo, Meilan Liu, Carlos Zerpa

ISBS Proceedings Archive

Concussions represent the second most common injury for ice hockey goaltenders. This study examined the combined effect of neck strength level and helmet liner type in mitigating concussion risk for ice hockey goaltenders. The researchers tested each helmet liner material statically for energy absorption capacity of the liner material, and dynamically by recreating concussion-causing events via head impact simulations for the risk of head injury criterion (HIC). The thermoplastic polyurethane (TPU) liner outperformed the standard vinyl nitrite (VN) liner during static testing and significantly reduced the HIC for high levels of neck strength (in newtons) during the repeated impact testing …

Go to article

Influence Of The Dame 8 Basketball Shoes On Jump Kinetics After 150 Miles Of Simulated Running, Jeremy Portillo, Giorgio Zucca, Karah Bell, Ernie Rimer, Adam Petway Jul 2023

Influence Of The Dame 8 Basketball Shoes On Jump Kinetics After 150 Miles Of Simulated Running, Jeremy Portillo, Giorgio Zucca, Karah Bell, Ernie Rimer, Adam Petway

ISBS Proceedings Archive

Basketball involves high-mileage running and repeated jumps. The goal of this study was to compare pre- and post-kinetic variables involved in jumping between basketball shoes with different inflicted mileage. Eleven NCAA Division I basketball athletes (20.5±1.4 years, 195.1±5.7 cm, 86.7±10.9 kg) performed a countermovement jump (CMJ), a rebound countermovement jump (CMJ-R), and a Multi-Rebound (MR) for four rounds on force platforms. Each round, athletes switched between brand-new (New) and worn (Worn) Dame 8 basketball shoes. Kinetic variables associated with each jump task were compared across shoe type. Several kinetic variables differed significantly between shoe type; however, the magnitude of difference …

Go to article

Estimating Lower Limb Joint Moments In Gait Using Common Machine Learning Approaches, Alex Ong Dr, Joseph Hamill Jul 2023

Estimating Lower Limb Joint Moments In Gait Using Common Machine Learning Approaches, Alex Ong Dr, Joseph Hamill

ISBS Proceedings Archive

The aim of this study was to investigate the efficacy of common machine learning algorithmic approaches to estimate lower limb joint moments during fast walking gait. Kinematic and ground reaction force data on 19 participants were captured with a force-plate and motion caption capture system. Inverse dynamics was used to calculate the right lower limb joint moments and common machine learning algorithmic approaches, such as Random Forest (RF), Linear Regression (LR), Neural Network (NN), AdaBoost (AB) and Gradient Boosting, were used to predict the corresponding joint moments using only the kinematic data. High coefficient of determination values (R2>0.9) …

Go to article

Pilot: Pitching Stride Characteristics Across An Apperance During A Division-I Collegiate Baseball Game, Bryson Nakamura Jul 2023

Pilot: Pitching Stride Characteristics Across An Apperance During A Division-I Collegiate Baseball Game, Bryson Nakamura

ISBS Proceedings Archive

Stride phase characteristics have been identified as contributors to pitch velocity. The aim of this study was to determine how in-game pitching stride phase characteristics and pitch velocity changed across a pitching appearance. Five (5) male Division-I pitchers were measured across an appearance during a collegiate baseball game. Five (5) biomechanical characteristics during the stride phase and pitch velocity were assessed. Biomechanical and pitch metrics were collected for each pitch and averaged per inning. Center of Mass Anterior/Posterior Velocity at Foot Contact was observed to significantly increase across time, though pitch velocity did not change across time. This may suggest …

Go to article

A Novel Study Examining Cognitive-Motor Interference After Anterior Cruciate Ligament Reconstruction, Alexander M. Morgan, Patrick S. Ledwidge, Justin Blankenburg, Jacob Petrus, Ryan Guggenheim, Harry Costlow, Alek Johnson, Jennifer Kadlowec Jul 2023

A Novel Study Examining Cognitive-Motor Interference After Anterior Cruciate Ligament Reconstruction, Alexander M. Morgan, Patrick S. Ledwidge, Justin Blankenburg, Jacob Petrus, Ryan Guggenheim, Harry Costlow, Alek Johnson, Jennifer Kadlowec

ISBS Proceedings Archive

The aim of this study is to assess the feasibility of examining cognitive motor interference (CMi) in athletes following anterior cruciate ligament reconstruction (ACLR) and return to sport through electroencephalography (EEG) and three-dimensional motion capture recordings. A 128-electrode EEG system is used to track brain wave patterns for specific biomarkers of CMi during sitting and balance tasks. An 8-camera Optitrack system is used to obtain three-dimensional kinematics during anticipated and unanticipated drop vertical jumps. Preliminary EEG N200 amplitudes (ACL: -4.99 ± 2.39; Control: -7.75 ± 5.83) and peak knee flexion (ACL: 93.29 ± 12.92°; Control: 92.87 ± 7.17°) during dual-task …

Go to article

Accuracy Of The Motusbaseballtm Wearable Sensor, Kane Middleton, Molly Connolly, Nicholas Busuttil, Michael Cianciosi Jul 2023

Accuracy Of The Motusbaseballtm Wearable Sensor, Kane Middleton, Molly Connolly, Nicholas Busuttil, Michael Cianciosi

ISBS Proceedings Archive

The purpose of this study was to assess the accuracy of the motusBASEBALLTM sensor. Trained/developmental male adult baseball pitchers (n = 10) threw ten pitches each from a regulation mound while kinematic and kinetic data were captured using an optical motion capture system and a motusBASEBALLTM sensor. Absolute and relative agreement were assessed. Outputs from the motusBASEBALLTM sensor were significantly different to the motion capture outputs for elbow varus torque, shoulder rotation, and arm speed (p < .05). Data were similar for arm slot (p = .847). Correlations (r) between system outputs were not significant (p > .05) and ranged from …

Go to article

“Tearing Up The Turf”: How Natural Grass Responds To Repeated Tractional Trials For Soccer Boot Analysis, Danyon Loud, Paul Grimshaw, Richard Kelso, Will Robertson Jul 2023

“Tearing Up The Turf”: How Natural Grass Responds To Repeated Tractional Trials For Soccer Boot Analysis, Danyon Loud, Paul Grimshaw, Richard Kelso, Will Robertson

ISBS Proceedings Archive

The shoe-surface interaction carries both performance and health-based implications for soccer players. As soccer is often played on natural grass surfaces, previous mechanical tests observing shoe-surface traction have examined the interaction on natural grass and reported averaged traction coefficient values. The aim for this study was to explore spatial changes within the playing surface, as well as examine if degradation over the testing period can alter these values. Through translational testing on a custom apparatus, this study showed that the average maximum traction coefficient on the same location of the playing surface was significantly lower than results reported at different …

Go to article

Impulse Generation And Initial Velocity Differences In Two-Foot Running Jumps With And Without A Basketball, Jun M. Liu, Antonia Zaferiou Jul 2023

Impulse Generation And Initial Velocity Differences In Two-Foot Running Jumps With And Without A Basketball, Jun M. Liu, Antonia Zaferiou

ISBS Proceedings Archive

This study aimed to (1) identify the roles of each leg in impulse generation and (2) determine differences in impulse generation and initial centre of mass velocities in two-foot running jumps with and without a ball. Eight recreational to collegiate basketball players performed three to ten repetitions of two-foot running jumps with and without a ball. We found that the first leg generated more backward and vertical impulse than the second leg in both two-foot running jumps with and without a basketball. Two-foot running jumps with a ball resulted in lower jump height and less vertical impulse generated by the …

Go to article

Movement Variability In Elbow And Wrist Kinematics Of New Ball Outswing Bowling In Cricket Fast Bowlers, Cody Lindsay, Rian Crowther, Kane Middleton Dr, Brad Clark, John Warmenhoven, Wayne Spratford Jul 2023

Movement Variability In Elbow And Wrist Kinematics Of New Ball Outswing Bowling In Cricket Fast Bowlers, Cody Lindsay, Rian Crowther, Kane Middleton Dr, Brad Clark, John Warmenhoven, Wayne Spratford

ISBS Proceedings Archive

This study investigated between-bowler movement variability of wrist and elbow kinematics during new ball swing bowling. A 3D motion analysis system captured the bowling action and ball trajectory of 11 pre-elite and elite fast bowlers delivering outswing. Kinematics were normalised to 100% of the delivery stride between back foot contact and ball release. A statistical parametric mapping approach using one-way ANOVAs investigated inter-individual movement variability. Significant differences were found in all kinematic parameters except for wrist radial/ulnar deviation angular velocity with bowlers using small amounts in either direction at the beginning of the phase. This study highlights that high-level athletic …

Go to article

Real-Time Backward Slip Detection Using A Slip-Inducing System And Machine Learning Methods, Chihyeong Lee, Jooeun Ahn Jul 2023

Real-Time Backward Slip Detection Using A Slip-Inducing System And Machine Learning Methods, Chihyeong Lee, Jooeun Ahn

ISBS Proceedings Archive

Wearable devices have been developed to assist walking based on the wearer’s intention. However, it would be dangerous if a device misidentifies falling as intentional motion; it is necessary to detect falls in real time. In particular, backward slip is the most common and dangerous type of falls. Fifteen participants walked on a split-belt instrumented treadmill while random backward slip perturbation of belt speed acceleration was provided to the foot. We aimed to identify slip within 0.35s after the onset of the perturbation, the typical window of slip, using lower limb kinematic data obtained within 0.3s; only 0.05s was allowed …

Go to article

An Investigation Into Seasonal Power Changes In Collegiate Baseball Pitchers, Suzanne M. Konz, Chris Lapole, Brandi Anders, Steve Leigh Jul 2023

An Investigation Into Seasonal Power Changes In Collegiate Baseball Pitchers, Suzanne M. Konz, Chris Lapole, Brandi Anders, Steve Leigh

ISBS Proceedings Archive

This study aimed to investigate changes in power and fatigue of collegiate baseball pitchers throughout a season to determine injury risk. Isokinetic, mobility, and performance test records were reviewed for 18 male NCAA-I baseball athletes. Testing was performed during the offseason, season start, and end of non-conference play and included medicine ball throws, hop testing, and 3-speed isokinetic testing. Statistical analysis determined that the kneeling medicine ball throw, 6-m hop, and several isokinetic outcomes decreased throughout the season. Using a combination of medicine ball throws, hop testing, and isokinetic testing at specific times during a season may provide insight into …

Go to article

Developing Methods To Assess The Relationship Between Ergometer And On-Water Rowing Performance From Independent Datasets, Sam Jones, Chris Bailey, Dave Thomas, Mark G. E. White, Paul Rees, Huw D. Summers, Neil E. Bezodis Jul 2023

Developing Methods To Assess The Relationship Between Ergometer And On-Water Rowing Performance From Independent Datasets, Sam Jones, Chris Bailey, Dave Thomas, Mark G. E. White, Paul Rees, Huw D. Summers, Neil E. Bezodis

ISBS Proceedings Archive

Rowing ergometers are often used by internationally competitive athletes alongside on-water rowing. This study proposes methods to develop a generalisable relationship between maximal effort 2000 m ergometer and on-water rowing performance using independent datasets. Ergometer times for 2000 m tests (n = 153) and 2000 m on-water times from international races (n = 139) were collated. Percentiles from the raw data and fitted probability density functions were mapped to develop a generalisable performance relationship. Bootstrapping was utilised to estimate the uncertainty in the percentile mappings. When built on a larger sample of athletes, this approach could be useful …

Go to article

Flipped Classroom For Undergraduate Introductory Biomechanics Class, Chengtu Hsieh Jul 2023

Flipped Classroom For Undergraduate Introductory Biomechanics Class, Chengtu Hsieh

ISBS Proceedings Archive

The purpose of this exploratory study was to examine the effectiveness of flipped classroom teaching approach in an undergraduate introductory biomechanics class. A total of 28 students were recruited for the study. Students were required to watch short videos, study reading assigned, and complete pre-work assignments before each class. During class time, students were mainly engaged with problem-based learning. The biomechanics concept inventory (BCI) version 3 was used to determine learning improvement. The pre-, post-test, and survey were administered during the first and last two weeks of the semester. Students demonstrated significant learning improvement (d = 1.23, P < 0.05) with a 23% normalised learning gain. Most students (64%) indicated that the flipped classroom approach works well for their learning because it provides flexibility that they may review the course lesson anytime on their own.

Go to article

Investigating The Performance Of Cycling And Hockey Helmet Liner Materials In Mitigating Impacts At Lower Speeds During Free Falls, Shrivatsa Hegde, Meilan Liu, Carlos Zerpa Jul 2023

Investigating The Performance Of Cycling And Hockey Helmet Liner Materials In Mitigating Impacts At Lower Speeds During Free Falls, Shrivatsa Hegde, Meilan Liu, Carlos Zerpa

ISBS Proceedings Archive

This study examined the performance of helmets made of expanded polystyrene (EPS) and expanded propylene (EPP) in mitigating linear impacts over three consecutive drop trials at 16 impact speeds ranging from 0.93 to 3.96 m/s. It was found that EPS, a liner material used in cycling helmets, had lower capacity of mitigating linear impact acceleration and captured a larger compressed area of impact than the EPPs, liner materials used for hockey helmets. EPS and EPPs all experienced some degrees of loss in their capacities to mitigate acceleration after the initial impact. All tested materials had no statistically significant difference in …

Go to article

Head Acceleration Events Using Instrumented Mouthguards In Female Ringette Players, Kenzie B. Friesen, Emily Hemming, Chris Dennison, Reed Ferber, Carolyn Emery Jul 2023

Head Acceleration Events Using Instrumented Mouthguards In Female Ringette Players, Kenzie B. Friesen, Emily Hemming, Chris Dennison, Reed Ferber, Carolyn Emery

ISBS Proceedings Archive

Ringette is a contact sport which prompts high rates of head contacts and concussion, some of the highest reported rates in youth sport. Biomechanical forces at the head can cause concussion injury, therefore examination of head acceleration events and head biomechanics during ringette is useful to understand injury risk and mechanism. The purpose of this study was to describe head acceleration events (HAEs) in female youth ringette players and examine head biomechanics during video-verified head acceleration events. Instrumented mouthguards were worn by 8 players and 36 video-verified HAEs were accumulated from in-game exposure. Results indicate athletes sustain HAEs from both …

Go to article

Effects Of Calf Anchoring Compression Levels On Ankle Kinematics, Motor Unit Behavior, Energy Cost, And Discomfort During Walking, Jaewoo Cho, Eunsik Choi, Sangheui Cheon, Seongwon Hwang, Jooeun Ahn Jul 2023

Effects Of Calf Anchoring Compression Levels On Ankle Kinematics, Motor Unit Behavior, Energy Cost, And Discomfort During Walking, Jaewoo Cho, Eunsik Choi, Sangheui Cheon, Seongwon Hwang, Jooeun Ahn

ISBS Proceedings Archive

We propose a method for quantifying the anchoring compression of wearable devices using limb occlusion pressure (LOP). Under 0%, 20%, 40%, and 60% of LOP, five healthy male participants performed an isometric ankle plantarflexion task before and after walking on an inclined treadmill. Significant differences were shown in calf discomfort (p < 0.001), and ankle plantarflexion angle (p = 0.013) during walking. Although no significant difference was found for oxygen consumption and motor unit behavior of the gastrocnemius medialis, the maintenance of ankle plantarflexion angle was related to an increase in peak motor unit action potential amplitude and average firing rate at 60% of LOP. The results suggest that subjective assessment is more sensitive than the physiological indices, and calf anchoring force should not exceed 60% LOP to avoid any possible negative effect on the muscle.

Go to article

Is Lateral Entry Beneficial To Elite Swimmers? A Preliminary Study, Chen Chen, Jie Gao, Boris Bačić, Shenghao Zhou Jul 2023

Is Lateral Entry Beneficial To Elite Swimmers? A Preliminary Study, Chen Chen, Jie Gao, Boris Bačić, Shenghao Zhou

ISBS Proceedings Archive

The purpose of this study was to improve performance of elite swimmers during the starting phase, by analysing whether the lateral entry technique is beneficial to athletes' starting. Participants’ (N=12) motion data were obtained from a 3D Performance Analysis System (Kistler 9691A1) with three cameras. Extracted 14 parameters were analysed using paired samples t-test. Differences contributing to the lateral entry performance included decrease of both entry angle and maximum depth by 1° and 0.42 m respectively (p<.01), and increase of push force by 0.08 of body weight (p<.01). The preliminary results show that the lateral technique provides a 0.06 s reduction in time to reaching the first 5 m (p<.05) compared to ordinary entry, suggesting performance improvements at start times.

Go to article

The Acute Effects Of A Grip-Constraint Tool On Upper Body And Racket Kinematics During Tennis Forehands, Nicholas Busuttil, Alexandra Roberts Dr, Marcus Dunn Dr, Kane Middleton Dr Jul 2023

The Acute Effects Of A Grip-Constraint Tool On Upper Body And Racket Kinematics During Tennis Forehands, Nicholas Busuttil, Alexandra Roberts Dr, Marcus Dunn Dr, Kane Middleton Dr

ISBS Proceedings Archive

The purpose of this study was to compare the acute effect of a grip-constraint tool on upper body and racket kinematics during tennis single-handed forehand strokes. Upper-body and racket kinematics for two grip conditions, Preferred (self-selected) and Grip-constraint tool (fixed semi-western forehand grip) were captured for eleven tennis players using a 22-camera Vicon motion capture system (240 Hz). Using a grip-constraint tool resulted in a more closed racket face tilt (~4°) at ball impact while having variations in joint rotations across the shoulder, elbow and wrist. This possibly demonstrates the participant’s ability to self-organise compensatory angular rotations across the upper …

Go to article

First Prev Next Last